This invention relates to a scroll compressor wherein the crankcase and the non-orbiting scroll are interconnected in a way that reduces assembly difficulties, and further reduces the possibility of weld spatter.
Scroll compressors are becoming increasingly popular for refrigerant compression applications. In a standard scroll compressor, a first scroll member is formed with a base and a generally spiral wrap extending from the base. A second scroll member has a base and a generally spiral wrap interfitting with the wrap of the first scroll member. The second scroll member is caused to orbit relative to the first scroll member and compression chambers defined between the two scroll members are reduced in volume to compress an entrapped refrigerant.
A crankcase supports the second scroll member, and sits on an opposed side of the second scroll member from the first scroll member. In some applications, the first scroll member is fixed relative to the crankcase. In other scroll compressors the first scroll member is allowed to move axially, but is prevented from orbiting or rotating. The crankcase is typically positioned relative to the first scroll member by dowel pins, or other structure extending between the two members. Alternatively, automated assembly and measurement equipment have been utilized to properly position the two components. These approaches have been somewhat complex and undesirable.
The standard crankcase includes a plurality of circumferentially spaced crankcase towers. These are structures extending axially beyond the second scroll member, which typically extend to be in close relationship with the first scroll member.
Scroll compressors are received in a sealed housing chamber. The housing chamber are formed of a central cylindrical shell which is welded to an end cap by a girth weld. The circumferentially spaced towers on the crankcase block the ingress of weld material, known as weld spatter, from moving between the end cap and the center shell into the housing chamber. However, the ingress of welding material does occur in the gaps between the crankcase towers.
The crankcase towers have a structural and casting function, and thus it would not be desirable to simply eliminate the crankcase towers, or to form them around the entire circumference of the crankcase.
The present invention is directed to eliminating the above-discussed challenges for scroll compressors.